Bellevue city officials attended Hansen's launching ceremony Saturday morning and congratulated him on his accomplishment in a Facebook post.
Hansen's journey aimed to break the Guinness World Record for longest journey by pumpkin boat, which was set at 25.5 miles by North Dakota man Rick Swenson in 2016.
"Congratulations Duane for smashing the world record," the City of Bellevue's Facebook post said. "We are proud that you started this record breaking 38 mile journey in Bellevue."
Evidence from Hansen's attempt must still be submitted to Guinness World Records for official recognition.